1. Field of the Invention
The present invention relates generally to building insulation. More particularly the present invention relates to a method and apparatus for installing insulation in the roof of a commercial or industrial building from above. The invention makes use of a new manner of anchoring the reinforced facing providing support for the insulation at the bottom.
2. Background Art
Fiberglass insulation has many advantages. It is not flammable, it provides good R-value, and it is nontoxic. It can be installed from below after the roof is finished to protect the insulating materials from the elements. It is also possible to install the insulation from above before the roof is sealed off. It is preferred to insulate new roofs from above for efficiency as well as the comfort of those carrying out the insulating.
Steel buildings typically have steel I-beam rafters running from an outside wall to the ridge of the roof. Attached to the top of these rafters and perpendicular to them are purlins. The purlins provide the structure to which the steel roofing is affixed. It is between the purlins, above the I-beam rafters and beneath the steel roofing that insulation is typically installed.
Installing insulation from above in new buildings is not new. An apparatus for dispensing insulation in the roof-section of industrial and commercial buildings from above is revealed in U.S. Pat. No. 5,921,057 by Alderman et al. The apparatus uses the purlins as tracks on which to run from one end of the building to the other. A support sheet, for providing support for the insulation at the bottom is also dispensed by the apparatus of U.S. Pat. No. 5,921,057. This support sheet is suspended from the tops of the purlins. Methods for anchoring the support sheet at intervals along the purlins for the purpose of keeping the support sheet tight and preventing pillowing are not described.
U.S. Pat. No. 5,636,487 to Fligg discloses an invention for insulating pre-existing roofs from below. It incorporates further support for insulating material between purlins as well as a method for anchoring a reinforced facing material support sheet at the ends. The method of anchoring the reinforced facing material is not immediately applicable to installation of insulation from above.
There is, therefore, a need for a method and device for anchoring supportive facing material when installing insulation from above in a steel building. Furthermore, there is a need for such anchoring to occur periodically across the building to reduce pillowing and improve the appearance of the insulating job from below.